Analytical evaluation of nebulizers for the introduction of acetic acid extracts aiming at the determination of trace elements by inductively coupled plasma mass spectrometry
| Autor: | Fernando Js Oliveira, Adilson J. Curtius, Tatiane de A. Maranhão, Vera L.A.Frescura, Daniel L. G. Borges, Jefferson Santos de Gois |
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| Rok vydání: | 2012 |
| Předmět: |
Detection limit
Analyte Chromatography Analytical chemistry Atomic and Molecular Physics and Optics Analytical Chemistry Bioavailability Nebulizer Acetic acid chemistry.chemical_compound chemistry Inductively coupled plasma atomic emission spectroscopy Leaching (metallurgy) Instrumentation Inductively coupled plasma mass spectrometry Spectroscopy |
| Zdroj: | Spectrochimica Acta Part B: Atomic Spectroscopy. 77:35-43 |
| ISSN: | 0584-8547 |
| DOI: | 10.1016/j.sab.2012.08.001 |
| Popis: | Most of the official procedures aiming at classification of solid waste toxicity take into account metal solubility and bioavailability by means of extraction experiments using acetic acid solutions. Hence, the aim of this work was to investigate and optimize conditions to suppress the effect of acetic acid on the determination of trace elements using inductively coupled plasma mass spectrometry. The performance of four nebulizers (cross-flow (CFN), ultrasonic (USN), Meinhard (MN) and MicroMist (MMN)) were compared as to their efficiency in minimizing spectral and non-spectral effects on the determination of Ag, As, Ba, Cd, Cr, Hg, Pb and Se, with the ultimate goal to analyze acetic acid extracts obtained from solid waste residues. Operating conditions (desolvation temperatures for USN, RF power and nebulizer gas flow rates) were optimized individually for each nebulizer and for all analytes maintained in 0.14 mol L − 1 HNO 3 solutions and in solutions prepared with acetic acid and acetic acid + NaOH, adjusted to pH 2.88 and 4.93, respectively. Pronounced non-spectral interferences for 75 As and 82 Se were observed in the presence of acetic acid for CF and MN, although to a less extent also for MMN and USN. Signal increase for blank solutions measured at m/z 208 ( 208 Pb) for CFN and MN, 107 ( 107 Ag) for USN and MN coupled to a cyclonic chamber and, m/z 82 ( 82 Se) for USN was observed, indicating an increased risk of spectral interference upon an increase in the concentration of acetic acid. Signal increase at specific m/ z ratios, however, was not significant when the MMN was used, with the exception of m/z 52 ( 52 Cr) in acetic acid solutions, arising from the formation of 40 Ar 12 C + . This same effect was noticed for all nebulizers, although at noticeably different intensities. A signal stability study was performed, demonstrating that variations in the analytical signal were within a 20% range for all analytes, with the exception of Hg, after continuous aspiration for 70 min. The nebulization efficiency ranged from 4.6% to 64% for CF and MM nebulizers, respectively. Leaching solution from a solid waste residue was analyzed using all the studied systems in three different calibration media. In general, the results indicate that calibration solutions should be prepared in the same medium as the leachate, although for USN and MMN a reasonable agreement among the results was obtained regardless of the calibration solution used. Detection limits ranging from 0.01 μg L − 1 to 2 μg L − 1 were obtained, with little discrepancy among the different nebulizers used. |
| Databáze: | OpenAIRE |
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